GOLDSCAN 5 SCHEMATIC QUESTION

[eclipse]

Now that you've mentioned version control...
I will upload versions of the schematic in github - https://github.com/ex3ek/Goldscan-5

[dbanner]

CD4046 chip, of course. This could work.

[Geo]

[QUOTE = Altra; 236761] Εδώ υπάρχει μια εικόνα TDI με NE5532. Ίσως μια φτηνή αντικατάσταση για τα NE5534 και AD8055; [/ QUOTE]

Also there is a 5534 near to connector.

[Geo]

Hi,
Would you post a picture of these part of the board ?
With a 5532 , there will only have 2 resistors by OPamp, and there will be close to circuit.

Maybe is a buffer at inverting operation

[Idefix]

Hi,
To Geo : the photo is with too low definition to see the value of smd resistor.
So if you can make a more close picture to the board, it will be better.
(go outside to have much mor light, it is better for picture sensors )

To Dbanner : my spice (Microcap Spectrum Software) version have plenty of component in library, but not the AD546.
I went on Analog web site, and there is not a space model.

I have V to F model, where I specify the sensivity. but it is a macro, only.
I can also make a generator with a user file (like an excel sheet) , and put this into the converter.

Ifyou have some scope traces of the input of the converter ( in different cases), it is possible to make a file and ther to do some runs )
I still go on looking for some models.

[gaby_sult]

CD4046 chip, of course. This could work.

yes .... it works very nice.

[dbanner]

Anyone here ever use QUCS simulation in linux. Seems to be quite good.

[6666]

Question for gurus: can a spice model be done for just the ad654, and how about using a regular 555 in its place? as i dont have ad654, i cant experiment.

I thought I found the right model but was wrong info,

[dbanner]

Thanks for help.

[Orbit]

There is more version ,I'm interested in how much noise there is ,on all metals and how much profit the GEB ??Gabi and Jose can see a video clip ?? If Altra can put the video its TDI proto ?!

I noticed that the differential integrator in the GS 4 application generate noise as well as the synchronization cd 4538 ! I think that's the main reason among other things applied by mcu as well as 4053 by TDI SL !


https://www.youtube.com/watch?v=dV-3yKez6YY My version 1.0 ]http://tinypic.com/r/2dbm06f/9

[Jose]

Thanks Orbita, for publishing the scheme.
There is little noise with a single channel, the noise increases when connecting the GB channel.
The high gain of the GB channel seems to be the main cause of the noise.
I do not know how to solve that problem, I was thinking of some type of LP filter as the QED uses, after the integrator, but I have not tested it.
Later I will make a video.
Jose

[Altra]

Orbit my unit sounds just like the unit in this video. When my unit is ground balanced it chatters more and mid range target like brass have very weak responses.
https://www.youtube.com/watch?v=ghxASe3pkqQ

Reg Sniff was doing mods on GS5's and early TDI's to reduce noise in the GB channel. It would be nice to figure out what he was doing.

Demonstration of noise reduction
https://www.youtube.com/watch?v=s0DXQFCF8F0

Reg talks a little about the noise reduction here.
http://australianelectronicgoldprosp...t-gen-tdi-pcb/

[Orbit]

Thank you Altra greetings to Jose ! I tried the filter to reduce noise and it is decreasing ,Noise is reduced totally ,but it also reduces profit with the included Geb !Noise is reduced if we reduce profits in the front !This video is not convincing me I have less noise on my design or similar to the video .

[Geo]

The mod by Reg works only at GEB mode and it increase the gain about 20%
At GEB=Off it works the same as before mod.

[Idefix]

Hi Altra,

I sent you a PM about your TDI . Have you have a look at what I said ?